1. Field of the Invention
The present invention relates to a polarizing plate composition, a polarizing plate protective film, a polarizer, a polarizing plate, and a liquid crystal display device.
2. Description of the Related Art
A polarizing plate consisting of at least a polarizer and a polarizing plate protective film is used as an optical member in various liquid crystal display devices.
In addition to a chance of using the liquid crystal display devices indoors in TV and the like, a chance of using them outdoor mainly in a portable device and the like is increasing. Therefore, the development of liquid crystal display devices usable at a higher temperature and humidity than those of the related art is being required.
Furthermore, liquid crystal display devices are increasingly required to be usable for more diversified purposes and be able to withstand severe service conditions. Accordingly, every year, the liquid crystal display devices are increasingly required to have durability higher than that of the related art.
In recent years, as the liquid crystal display devices used mainly in TVs have become bigger and thinner, a polarizing plate including a polarizing plate protective film that is a constituent member has also been required to become thinner. From the viewpoint of workability, an appropriate hardness and excellent cutting properties have been emphasized for the polarizing plate protective film, and further improvement of those properties is required for the thin polarizing plate protective film.
Regarding a polarizing plate protective film using a cellulose acylate film, as a solution to various issues relating to the further improvement of the performance and the properties or manufacturing of the polarizing plate protective film, a method of causing the film to contain a specific compound is known.
For example, in order to inhibit an environmental humidity-dependent variation of retardation of the polarizing plate protective film, an organic acid compound having a pKa value of 2 to 7 is suggested (see JP2011-118135A).
Meanwhile, in order to improve a transverse variation of retardation, a method of using a deterioration preventive agent having hindered phenol and hindered amine in the same molecule is suggested (see JP2002-121459A). Furthermore, for color filters, a method of using a specific pigment dispersant is suggested (see WO2006/115015A).